Fluid-reaction propelling apparatus



Oct. 29, 1935. H. ENDRES 2,018,779

FLUID REACTION PROPELLING APPARATUS Filed Au 13, 1954 s Sheets-Sheet 1 fm ew for:

HANS ENORES ATTORNEY Oct. 29, 1935. ENDRES 2,018,779

FLUID REACTION PROPELLING APPARATUS Filed Aug. 13, 1954 3 Sheets-Sheet 2 200 v FIE-Q 300 Fl E i ATTOR EY Oct. 29, 1935. H. ENDRES FLUID REACTION PROPELLING APPARATUS Filed Aug. 13, 1934 3 Sheets-Sheet 3 Flljj UUUUUUIW EN-mass Y ATTORNEY HANS Patented Oct. 29, 1935 UNITED, STATES PATENT OFFICE FLUID-REACTION PROPELLING APPARATUS Hans Endres, Solingen, Germany, designer of onehalf to Emanuel Bachmann, Los Angeles, Calif.

Application August 13, 1934, Serial No. 739,705

- In Germany August 15, 1933 16 Claims.

used for vehicles on roads, for ships, or for powergenerating plants of any kind, but is particularly useful in the propulsion of aircraft.

The efficiency of the usual helical propellers for aircraft is very poor, and the speed they impart is comparatively low. Fluid-reaction propelling apparatus as designed heretofore, i. e., with a single nozzle for ejecting a stream of compressed air, might be used for the propulsion of aircraft but their demand of compressed air is so high that the power input is almost equal to that" of a helical propeller. This is due to the fact that only about 5% of the kinetic energy in the stream of compressed air is utilized for propulsion, and about 95% is lost. Apart from its low efliciency, the fluid-reaction apparatus is preferable to the helical propeller on account of its simplicity. It does not require an elaborate power plant, with internal-combustion engines, reduction gears, etc, and does away with all the dimculties and risks of such a plant.

It is the principal object of my invention to so design a fluid-reaction propelling apparatus that its efiiciency is far superior to that of the singlenozzle apparatus referred to, aswell as to the efiiciency of the helical propeller while at the same time my novel apparatus is almost as simple as the one with the single nozzle.

To this end, I provide a jet, means for discharging a stream of fluid under pressure, norin which the stream issues from the nozzle, 1. e.,

this nozzle is at the rear end of the apparatus, and the jet from which the stream is primarily discharged, is in front of the nozzle.

Preferably, I provide a set of subsidiary nozzles between the nozzle at the rear end, or last noz- 1 zle, and the jet. The outlet pipes of the nozzles are arranged co-axially with respect to the jet, and to each other, and are so nested one within the other that the vacuum gradually increases and becomes a maximum in the first subsidiary nozzle. The areas of the annular clearances defined by the outlet pipe of the first subsidiary nozzle, and the outlet end ofthe jet, and by each pair of nested outlet pipes, increase progressively toward the rear of the apparatus, as required by the expansion of the streaming fiuid.

I provide a compressor at or near the front end of the apparatus, and a piston which subdivides the compressor into a compression and a suction chamber. The jet is connected to the compression chamber, and the nozzle-or the first sub- 1 sidiary nozzle, is connected to the suction chamber of the compressor. The pistonis reciprocated by the difference of the pressures acting on opposite sides thereof, and controlled by means such as ports in its skirt, and corresponding ports 15 in the wall of its cylinder.

My invention will be more fully understood from the following detailed description and the drawings in which three types of apparatus embodying my invention are illustrated by way of example.

In the drawings Fig. 1 is an axial section,

Fig. 2 is a rear-end elevation,

Fig. 3 is a front-end elevation, and 25 Fig. 4 is a section on the line IV-IV in Fig. 1; showing the first and simplest type in which a single compressor piston is provided and a supply of compressed fluid, normally air, is controlled by the compressor piston;

Fig. 5 is an axial section,

' Fig. 6 is a rear-end elevation,

Fig. 7 is a section on the line VIIVII in Fig. 1, and

Fig. 8 is a front-end elevation; showing the sec- 0nd type in which the compressor piston is subdivided into a principal piston and a set of auxiliary pistons, all on a tubular piston rod, and the principal piston controls the supply of driving fluid,

Fig. 9 is an axial section, and

'Fig. 10 is a rear-end elevation; showing the third type in which the compressor piston is subdivided, as in the second type, but the principal and auxiliary pistons are on a solid piston rod, and a separate piston is placed on the rod for controlling the supply of driving fluid,

Fig. 11 is an elevation of a ported sleeve on the compressor cylinder,

Fig. 12 is an elevation of a ported rotary valve for controlling the ports in the sleeve, and

Fig. 13 is an elevation of a cam for controlling the rotary valve, of the third type.

Referring now to the drawings, and first to Figs. 1 to 4, the parts of the apparatus are housed in a casing I whose rear end supports the last nozzle 2, with its outlet pipe 200. A compressor cylinder 3 whose outside diameter is smaller than the inside diameter of easing I, is screwed into the front end of the casing on whose edge it bears with a flange 4. 5 are bores in the wall of cylinder 3 which, as shown in Fig. 4, are arranged on a circle about the axis of the cylinder, and are open to the atmosphere, or to the relative wind in the case of aircraft, at their outer ends while their inner ends are connected to a row of ports 6 in the wall of cylinder 3. Another row of ports arranged at the rear of ports 6, connects the in-- terior of the compressor cylinder 3 to the annular space it defines within the casing I. Arranged still further to the rear is an annular groove 8 in the piston-swept inner surface of the cylinder, and 9 and I are pipes for supplying fluid driving medium, normally air under pressure, to the groove 8 from a suitable source, not shown. A plug II closes the compressor cylinder 3 at its front end, and a cover I2 is placed on its rear end. Inserted in this rear end is the base of a tapered let I3, whose outlet end I30 extends to the rear. A casing I4 is also inserted in the cover I2 and supports a check valve I5 which opens into the cylinder 3, and spring I6 serves for seating the valve. A pipe I I which extends through the wall of casing I, is connected to the valve casing I4 at its inner end while its outer end opens into the atmosphere. The check valve I 8 serves for admitting make-up air to the cylinder, as will be described.

Mounted to slide in the compressor cylinder 8 is a tubular piston I8 with a web I9 which subdivides the cylinder 3 into a compression chamber 0 at the rear, and into a suction chamber 8 at the front end of the cylinder. Rows of ports 66, 2i and 20 are formed in the skirt of the piston I8 for controlling, respectively, the rows of ports 8 and I, and the groove 8. It will appear that ports 88 and 2I are in the suction, and ports 28 are in the compression chamber.

A spring 22 is placed in the suction chamber 5 within the tubular front portion of piston I8 upon whose web I9 its rear end bears. The front end of the spring is supported by a spring plate 23 at the inner end oi a spindle 24 which is inserted in a female thread of plug II with its threaded portion, and equipped with a square portion 25 at its outer end for turning it and adjusting the tension of spring 22.

A set of subsidiary nozzles 28, with outlet pipe 268; 27, with outlet pipe 218: 28, with outlet pipe 288: and 28, with outlet pipe 290; is inserted in the casing I between the jet I3 and the last nozale 2. The outlet pipes of the nozzles are tapered and nested as shown, and their tree sectionall areas increase from the front toward the rear, the area of the outlet pipe 208 01' the last nozale 2 being largest. In the same proportion, the annular spaces defined by two nested outlet pipes, increase toward the rear. The ratio at which the free sectional area of the nozzles increases, and the number of subsidiary nozzles provided; is determined by the degree of expansion of the stream from jet II. The bodies oi. the last nozzle 2 and oi the subsidiary nozzles 28 to 29 are fun nel shaped with curved walls, and their largest diameter is equal to the inside diameter of casing I. The volume of the compartments defined by two adjacent nozzles is a function 01' the ratio of the free sectional areas of their nested outlet pipes.

It will appear that the outlet pipe 280 of the first subsidiary nozzle 26 surrounds the end I30 of the jet I8, the rear end 260 of the outlet pipe 5 projecting beyond the rear end 230 of the jet. The outlet pipe 210 of the second subsidiary nozzle 2 I is in a similar position with respect to the outlet pipe 260 of the first one, and so on.

The compartments defined by the individual nozzles are not connected to the atmosphere directly but only through the outlet pipe 200. of the last nozzle 2.

The operation of my apparatus is as follows:-

In the initial position of parts, as shown in Fig. 1, the spring 22 is fully expanded and the piston I8 is at the rear end of its stroke toward the compression chamber C. Its skirt lays open the ports I and the groove 8 but closes the ports 68. The check valve IS in the rear cylinder cover I2 is closed by its spring I8.

For starting the apparatus, fluid under pressure, normally compressed air, is admitted to groove 8 through pipes 9 and Ill. The air is admitted to the compression chamber C through the 2 ports 28 in the skirt of the piston I8, produces a certain pressure in the chamber C and flows out through jet I8, its pressure being transformed into velocity. The primary stream from jet I3 produces reaction and, through the nested outlet pipes .260, etc., accelerates the air in the compartments defined by the nozzles of the set, producing secondary flows. The partial vacuum produced by the primary stream from jet I3 is a maximum in the first nozzle 26. This vacuum which, due to the cooperation of the several nozzles, may be lowered almost to an absolute vacuum, gets to the ports 1 in the cylinder 3, and, through ports H in the piston skirt, into the suction chamber S. The reduction oi pressure in suction chamber S, and the higher pressure in chamber C, cooperate to throw the piston I8 as far as the front end of its stroke, compressing spring 22, closing ports I and groove 8, and open ing ports 8., Air, or relative wind, now enters the suction chamber S through bores 5, ports 6 and 66, and atmospheric pressure-or the pressure of the relative wind-is established in suetion chamber S. Spring 22 which had been compressed by the reduction of the pressure in suction chamber S, is now free to expand, and throws the piston I8 back to the rear end of its stroke, compressing the air in compression chamber C and ejecting it through jet I3, until the piston I8 has returned into its initial position and the 65 apparatus is ready for the next cycle. The groove 8 in the compressor cylinder again registers with the ports 20 in the piston, as shown in Fig. 1, and a fresh supply of compressed air is admitted. Air for making up the volume required for producing the stream from jet I3 is drawn into the compression chamber C through check valve I5 when the piston moves in forward direction. The free sectional area of the check valve is overdimensioned to avoid return flow of air. The apparatus now keeps going until the supply of compressed air is cut ofi. When this occurs the apparatus does not stop immediately but continues its operation for some time until the vacuum has become exhausted.

The theory of the apparatus will now be explained. In addition to the intermittent flow of driving fluid from pipes 8 and I8 under the control of the piston, through the ports 20 in its 75 skirt, three more intermittent flows of air are established in the apparatus as follows:

1. Drawing in make-up air through valve l5. This air which may be under the pressure of relative wind, is compressed in chamber C and discharged intermittently from jet 3 as the primary stream after the supply of driving fluid through parts 20 has been cut ofi.

2. Access of the partial vacuum produced by the primary stream to suction chamber S and outflow of the air from such chamber.

3. Admissionof relative wind to suction chamber S through bores 5.

The apparatus may be defined as a hollow member which is not accessible to atmospheric air directly. During the compression stroke of piston l8, air is expelled from the apparatus by the stream from jet I3 issuing through the outlet pipe 200 of the last nozzle 2. During the make-up stroke of the piston, i. e., during its movement to the forward end of its stroke, the stream from pipe 200 is interrupted and an indirect connection of the subsidiary nozzles to atmosphere is established but, due to the overdimensioning of check valve i5, there is no return flow of air through outlet pipe 200 and the set of nozzles.

The kinetic energy of the stream from jet I3 is transformed into reduction of pressure in the nozzles. The partial vacuum thus produced is transferred to suction chamber S, causing the pressure in compression chamber 0 to compress spring 22. When air, or relative wind, is admitted through bores 5, the spring 22 expands, throwing the piston I8 to the rear and expelling the air from compression chamber C through jet l3. When the piston moves in forward direction and compresses spring 22, make-up air is drawn into compression chamber C through check valve IS.

The principle of reaction propulsion on which my invention is based, is the production of pressure differences by gas or air under pressure issuing from a nozzle, which differences become active as thrust forces. It is known from the theory of aviation that such differences of pressure acting on a surface, may be very eflicient. Thus, in a flying airplane, the pressure of the ambient air is reduced above, and increased below, the wings of the plane. The higher pressure acting on the wings in vertical direction from below, produces the lift of the plane. By the reaction apparatus according to my invention, such pressure differences may be produced in horizontal direction, and high speeds attained, as only the aerodynamic resistance has to be overcome. Reaction propulsion, as mentioned, is entirely practicable in aircraft, but has failed on account of its low efficiency.

I obtain high efliciency by utilizing the vacuum the stream from jet I3 produces, and, by providing a set of nozzles as described, the pressure in the individual compartments defined by the nozzles is progressively reduced, the partial vacuum in each nozzle intensifying the partial vacuum in the other nozzle in whose outlet pipe the outlet pipe of the first-mentioned nozzle is nested, and the partial vacuum produced may become almost equal to the absolute vacuum, as mentioned above.

This mode of operation is quite novel and very efficient. 1

The only losses occurring in my apparatus are the friction losses in the jet, the nozzles and the compressor cylinder which may be estimated as 5%, and 95% of the available energy are utilized,

as against the helical propeller in which the major portion of the energy is wasted.

My invention revolutionizes the art of producing thrust for propulsion, and opens quite novel aspects in the development of airplanes. My 5 novel apparatus is extremely simple as against the usual power plant of an airplane, is absolutely reliable and gives maximum efficiency, so that the highest speeds are attainable therewith.

The paramount importance of my invention 10 will be fully realized if it is considered that in my apparatus the relative wind is utilized very extensively for producing thrust force, which is impossible in a helical propeller as the circular area swept by its blades presents an extra re- 15 sistance surface.

As the velocity increases, the relative wind and the volume of air admitted to the compression chamber 0 increase also, and it follows that the compression in the apparatus, and the thrust, ingo crease with the velocity of the airplane or airshp. Relative wind increases with the square of the velocity while reaction is directly proportional to velocity. There is a limit at which relative wind becomes equal to reaction, but this 25 limit is a velocity much higher than the velocities attainable in propeller-driven aircraft.

Apparatus according to my invention are arranged at as many points of the aircraft, for instance, on the fuselage and the wings of an 30 airplane, as may be required for eliminating one-sided stress on the parts, and for uniformly distributing the thrust forces. By regulating the individual apparatus, the production of reaction forces is adapted to existing flying conditions 85 at any time.

In particular, my invention is very favorable for starting and landing, as, by turning the apparatus into vertical position, vertical forces are produced for lifting the airplane from the 40 ground, and for decelerating its descent when landing. The lift is independent of the suction at the upper faces of the wings, and the necessity of providing long runs for starting and landing is eliminated. 45

My apparatus is first and foremost designed for the propulsion of aircraft but, as mentioned,

it may also be used for propelling road vehicles end it is secured by a flange 3i, and the casing l 3 and cylinder 3 are surrounded by a vacuum jacket 32.

The rear cover I2 is not placed on, but inserted in, the cylinder 3 ahead of flange 3|, and cupped at its centre for the reception of jet I3. 55 A piston valve 33 is mounted to slide with its boss on a cylindrical portion of the jet I3, and provided with a row of ports 34. The piston valve 33 is forced against an inwardly projecting rim of flange 3| by a spring 36 and in 70 this position of the piston valve, its ports 34 register with ports 35 in the wall of the cylinder which connect the body of the first subsidiary nozzle 26 to the vacuum jacket 32 through ports 34. The front end of spring 36 is supported by the rear cover l2. Ports 31 connect the space vacuum fluid supply pipes 9 and II) are connected, and the ports 3 for admitting relative wind through bores 5.

In this type, however, the piston I8 is only the principal piston of a piston unit comprising, in addition to the principal piston I3, three auxiliary pistons 5|, 52 and 53 which, together with piston l8, are secured on a tubular piston rod 33. The front end of piston rod 38 which is larger than its rear end so that the rod tapers like a nozzle, is equipped with a flange 39 bearing on the rear end of spring 22 whose front end is supported by an annular flange 40 at the front end of cylinder 3. A tube 4| extends to the rear from flange 40.and an extension 42 of the piston rod 38 is fitted to slide in the rear end of the tube.

In this type, make-up air is drawn in through the tubular piston rod 38. A cylinder 43 which is open at both ends, is inserted in the tube 4| and spaced therefrom to form an annular airinlet passage 44. A transverse rib 45 closes the passage 44 at the rear and holds the cylinder in the tube. A piston 46 is mounted to slide in the cylinder 43, and is forced against a check at the rear end of the cylinder by a spring 41. In this position of the piston, ports 49 in the piston register with ports 50 in the cylinder 43 so that the air, or relative wind, is admitted to the interior of piston rod 38 through passage 44, ports 49, 50 and the open rear end of the cylinder 43.

Three auxiliary pistons 5|, 52 and 53 are secured on the hollow piston rod 38. At the rear of every auxiliary piston, a partition 56, 55a, and 56b, respectively, is arranged and secured in the cylinder 3 at its outer perimeter. The partitions are cupped toward their centres so as to resemble nozzles, and their rear ends make a tight fit on cylindrical portions of the piston rod 38. Ports 51, 51a. and 511) are formed in the piston rod 33 at the rear of each auxiliary piston. The front end of the cylinder is closed by a partition or annular cover 58 which resembles the partitions 53 etc. The skirts of the auxiliary pistons have ports 54, 62 and 63, respectively, for cooperation with ports 55, 53 and 80 which are connected to the bores 5.

The partition 58 and the first auxiliary piston 5| deflne together the first suction chamber Sn,

and the piston 5| and the partition 53 define together the first compression chamber Ca. Similarly piston 52 and partition 56 define the second suction chamber Sb, and piston 52 and partition 56a deflne the second compression chamber Cb.

The third suction chamber So is defined by 53a and piston 53. The third compression chamber Co is defined by piston 53 and partition 55b. The

fourth suction chamber Sd is defined by partithe vacuum jacket 32, ports 20 connect the groove 3 to the last compression chamber Cd.

and the ports la etc. are exposed by the skirts of the respective auxiliary pistons, and the skirt of principal piston I3, for connecting the suction is chambers Sa etc. to the vacuum jacket 32. Piston 46 in cylinder 43 admits air to the interior of piston rod 38 which is connected to compression chambers Ca to Cc by the ports 51, 51a, etc. in the piston rod, and to compression chamber 10 Cd by the open rear end of piston rod 38. The ports 55 etc. for admitting air to the suction chambers, are closed by the skirts of the respective pistons.

The compressed air from pipes 9 and I0 starts 15 the apparatus, as described with reference to Figs. 1 to 4. The stream issuing from jet l3 produces a partial vacuum which is transferred to the vacuum jacket 32 through ports 34, 35 in piston valve 33. The jacket is connected to the 20 space between piston valve 33 and cover l2 by ports 31, and to the individual suction chambers 80. etc. through ports la etc. The pressure in compression chamber Cd which is partly transferred to the other compression chambers Ca to 25 Ce through ports 51 etc., throws the pistons toward their foremost position, while spring 22 is compressed. The forward or suction movement of the pistons closes groove 8 and interrupts the supply of compressed air to compression cham- 30 her Cd. The air under pressure flows out from the several compression chambers through jet l3. When the stream from jet l3 ceases to flow, the piston valve 33 disconnects the ports 34 and 35. While'the pistons move in forward direction, air 85 or relative wind is admitted to the individual compression chambers through passage 44 and the hollow piston rod 33. Ports la etc. are closed by the skirts of the respective pistons, and the partial vacuum still present in the suction cham- 40 bars Sa etc. moves the pistons into their foremost position in which their skirts expose the ports 55 etc. so that air or relative wind from bores 5 is admitted to the suction chambers and the partial vacuum therein is broken. Spring 22 I is now free to expand and throws the pistons to the rear,compressing the air in the compression chambers. The compressed air is ejected through jet l3, and reacting on piston 46, causes it to close the air-inlet ports 50. Finally, the 50 parts return into their initial positions shown in Fig. 5, and are ready for the next cycle.

By the combination of pistons and nozzles in series, as described, the kinetic energy of the stream issuing from jet I3 is utilized for com- 35 pressing the fluid in the apparatus and the loss of the system is reduced to a minimum.

Equalization of the vacuum in the nozzles with atmospheric pressure cannot occur, as the individual impulses of the stream from jet l3 occur so rapidly that the action of the intermittent stream is practically equal to that of a continuous one, and return flow of air is prevented.

Referringnow to Figs. 9 to- 13, the casing I with its nozzles is designed exactly as described with reference to Figs. 5 to 8, apart from the fact that it has six subsidiary nozzles instead of five, as in Figs. 5 to 8. Obviously, the number of the nozzles as well as that of the suction and compression chambers, may be varied as desired 7 in any type of my apparatus.

The cylinder 3 is connected to the front end of casing l by flanges 3|, and the cylinder and easing are surrounded by the vacuum jacket 32. as inthe second type. The rear cover H, the jet I3, and the piston valve 33, are also designed as in that type.

A tapered cowl 64 is placed on the cylinder 3 at the rear of ports 6| and a sleeve 80, with three rows of ports 8|, 82 and 83, is secured to the wider front end of cowl 64 at 11. The sleeve surrounds the front end of cylinder 3 in spaced relation and at its own front end supports a cover I9 by flanges I8. The piston I8 by which the starting air from pipes 9 and I0 is controlled, is mounted in an extra cylinder 64' on the cover I9. The rod of piston I8 is a solid member 65 and surrounded by spring 22 whose front end is inserted in a socket at the centre of cover 19 while its rear end bears against the first piston 61 of the set on red 65. The set includes four pistons, 61, 68, 69 and I0 which are not auxiuary" pistons as they do not cooperate with a principal piston, the piston I8 being arranged at the opposite end of cylinder 3. The pistons are annular members, each with a tubular boss II, I2, 13 and 14, respectively which are spaced from the piston rod 65 and connected to it by spiders I5. The pistons, with partitions I6, 11 and I8 in the cylinder 3, define the suction chambers Sa to Sd, and the compression chambers C0. to Cd. The tubular bosses of the pistons make a sliding flt in the partitions. Ports 55, 59, 60 and GI connect the interior of cylinder 3 to the interior of cowl 64.

A rotary valve 84, with three rows of ports 85,

86 and 81 in line with rows 8I, 82 and 83 of the sleeve 80, is inserted in the sleeve and, with its web 88, is mounted for rotation in antifriction bearings 92 and 93. The bearing 92 which is in front of the web 88, is supported by a spring 9| on the cover 19, and the rear bearing 93 is secured to a flange 90 at the front end of cylinder 3. A cam 94, with camming members 95 and 96 at opposite ends, is placed on the tubular boss H of the first piston 61 so as to rotate thereon. and is equipped with a flange 91 for engaging the web 88 of rotary valve 84. A pin 98 is arranged at the rear, and a pin 99 is arranged in front, of the cam 94.

The cylinder 64' of the starting piston I8 has a row of ports I00 which open into a tube I02 surrounding the cylinder. This tube is connected to the chamber of the rotary valve 48 by ports I03 in the cover I9.

In the initial position illustrated in Fig. 9, the ports 20 of piston I8 are in line with the groove 8, as described. When driving fluid is admitted, the piston I8 moves in forward direction and pulls the set of pistons 61 etc. in the same direction. Spring 22 is compressed. The valve 84 is so positioned that its ports 85 register with the ports 8| of the sleeve 80, and its ports 81 with the ports 88 of the sleeve, while ports 86 and 82 are out of register. The forward movement of the set of pistons increases the volume of compression chambers Co to Cd, and air, or relative wind, is admit-' ted to, and drawn into, the chambers through ports BI, 85 and the tubular bosses of the individual pistons. The suction chambers So to Sd are connected to the vacuum jacket 32 through ports 55 etc., and ports 83, 81 of the sleeve and the rotary valve.- The air from the suction chambers is evacuated through ports 55 etc. and into jacket 32, and the accelerating movement of piston I8 is assisted by such evacuation. The, ports 34 of piston valve 33, and 36 of cylinder 3, are out of register so that the vacuum in jacket 32 is not transferred to the first subsidiary nozzle 26.

Shortly before the pistons arrive at the foremost end of their stroke, the rear edge of piston I8 exposes ports I00 so that the air from cylinder 64' flows into the compression chambers through tube I02 and ports I03. At the same time, the pin 98 on boss ll of pistons 61 engages the camming member 96a and turns the rotary valve 84 to close ports 8i and 83, and to open ports 82 of sleeve 80. overthrowing of the valve 84 is prevented by the vertical edge 95b of the subsequent camming member 95. Air or relative wind is now admitted to the suction chambers Sa etc. through ports 55 etc. and spring 22 now throws the pistons to the rear, compressing the air in the compression chambers Ca etc., and ejecting it through jet I3 as described. Shortly before the pistons arrive at the rear end of their stroke, the rotary valve 84 is reversed by pin 99 engaging a camming face 9611 on one of the camming members 96. The apparatus is now ready for the next cycle.

It will appear that the hollow bosses II etc. of the pistons 67 etc. make up a passage for the air admitted to the compression chambers Ca etc., which passage opens into the jet I2. Any suitable means may be provided for connecting the bosses to the piston rod, for instance, steel ribs, not shown. Obviously such means must not interfere with the flow of the air in the tubular bosses.

By the means described, the streams and forces established in the apparatus, i. e., the partial vacuum and the relative wind produced by the stream from jet I3 and by the velocity of the aircraft, respectively, are controlled and utilized for producing thrust. The rotary valve 84 is rotated uniformly and its operation is absolutely reliable, as the stress on the members of this simple valve gear is quite negligible as compared with the usual valve gears of internal combustion engines.

A particular drawback of such valve gears is that considerable masses must be speeded up during a very short period. This is why the usual valve gears are limited to speeds of the order of about 4000 revolutions per min.; much higher speeds can be attained with the rotary valve according to my invention. The velocity imparted to aircraft is limited only by the equalization of the reaction produced in my apparatus, and of relative wind, as explained above, and this limit is much higher than the normal speeds of airplanes and airships.

I claim:

1. In a fluid-reaction propelling apparatus, a. compressor, a member which subdivides said compressor into a suction and a compression chamber and is movable under the influence of the pressures acting on opposite sides of the member, a jet connected to said compression chamber for discharging a stream of fluid therefrom, a nozzle which is so arranged with respect to the jet that the stream produces a partial vacuum in the nozzle, and means operatively connected to said member so as, by movement of said member, to alternately connect said compression chamber to a supply of fluid under pressure and to cut off the connection, to connect said suction chamber to the partial vacuum in said nozzle when the connection is established, and to connect said suction chamber to the ambient air when ber, a jet connected to said compression chamber for discharging a stream of fluid therefrom, a principal nozzle at the rear end of the apparatus,

an outlet pipe on said nozzle arranged co-axially to said jet for conducting the stream into the open airsothatitproducesapartialvacuuminthe principal nozzle, a set 01 subsidiaiy nozzles arranged between said principal nozzle and said jet, an outlet pipe on each nozzle arranged co-axially to said jet and to the outlet pipe the principal nozzle, the outlet pipes oi the nozzles being so nested with respect to each other and to said jet, that the partial vacuum is gradually increased from said principal nozzle to the first subsidiary nozzle, and means operatively connected to said movable member so as, by movement of said memher, to alternately connect said compression chamber to a supply or fluid under pressure and to cut oil the connection, to connect said suction chamber to the partial vacuum in said first subsidiary nozzle when the connection is established, and to connect said suction chamber to the ambient air when the connection is cut oil.

3. In a fluid-'reaction propelling apparatus, a compressor, a member which subdivides said compressor into a suction and a compression chamber and is movable under the influence of the pressures acting on opposite sides of the member, a jet connected to said compression chamber for discharging a stream of fluid therefrom, a principal nozzle at the rear end of the apparatus, an outlet pipe on said nozzle arranged coaxiaily to said jet for conducting the stream into the open air so that it produces a partial vacuum in the principal nozzle, a set of subsidiary nozzles arranged between said principal nozzle and said jet, an outlet pipe on each nozzle arranged coaxially to said jet and to the outlet pipe of the principal nozzle, the outlet pipe of the principal nozzle having the largest, and the outlet pipe of the first subsidiary nozzle having the smallest diameter, and the diameters of the intermediate nozzles having intermediate values; and the outlet pipes of the nozzles being so nested with respect to each other and to said jet, that the vacuum is gradually increased from said principal nozzle to the first subsidiary nozzle, and means operatively connected to said movable member so as, by movement of said member, to alternately connect said compression chamber to a supply of fluid under pressure and to cut oil! the connection, to connect said suction chamber to the partial vacuum in the first subsidiary nozzle when the connection is established, and to connect said suction chamber to the ambient air when the connection is cut oil.

4; In a fluid-reaction propelling apparatus, a compressor, a member which subdivides said compressor into a suction and a compression chamber and is movable under the influence of the pressures acting on opposite sides of the member, a jet connected to said compression chamber for discharging a stream of fluid therefrom, a principal nozzle at the rear end of the apparatus, an outlet pipe on said nozzle arranged co-axially to said jet for conducting the stream into the open air so that it produces a partial vacuum in the principal nozzle, a set of subsidiary nozzles arranged between said principal nozzle and said jet, an outlet pipe on each nozzle arranged coaxially tosaid jet and to the outlet pipe of the principal nozzle, the outlet pipe of the principal nozzle having the largest, and the outlet pipe of the first subsidiary nozzle having the smallest diameter, and the diameters oi the intermediate c mm nozzles having intermediate values; and the outlet pipes of the nozzles being so nested with re- I spect to each other and to said jet, that the vacuum is gradually increased irom said principal nozzle to the first subsidiary nozzle, the 5 number of said subsidiary nozzles, the ratio of the diameters of their outlet pipes, and the volumes oi the compartments defined by the nozzles, being determined by the degree of expansion of the stream, and by the ratio of the free sectional areas of said outlet pipes; and means operatively connected to said movable member so as, by movement of said member, to alternately connect sai'd compression chamber to a supply of fluid under pressure and to cut oil the connection, to connect said suction chamber to the partial vacuum in the first subsidiary nomle when the connection is blished, and to connect said suction chamber to the ambient air when the connection is cut oil.

5. In a fluid-reaction propelling apparatus, a compressor, a member which subdivides said compressor into a suction and a compression chamber and is movable under the influence oi the pressures acting on opposite sides of the member, a jet connected to said compression chamber for discharging a stream of fluid therefrom. a principal nozzle at the rear end of the apparatus, an outlet pipe on said nozzle arranged co-axially to said jet for conducting the stream into the open air so that it produces a partial vacuum in the principal nozzle, a set of subsidiary nozzles, each with a curved and funnel-shaped body, a tapered outlet pipe on each nozzle arranged coaxially to said jet and to the outlet pipe of the principal nozzle, the outlet pipes of the nozzles being so nested with respect to each other and to said jet, that the vacuum is gradually increased from said principal nozzle to the first subsidiary nozzle, and means operatively connected to said movable member so as, by movement of said member, to alternately connect said compression chamber to a supply oi fluid under pressure and to cut ofi. the connection, to connect said suction chamber to the partial vacuum in the first subsidiary nozzle when the connection is established, and to connect said suction chamber to the ambient air when the connection is cut oil.

6. In a fluid-reaction propelling apparatus, a casing, a compressor in said casing, a member which subdivides said compressor into a suction and a compression chamber and is movable under the influence oi the pressures acting on opposite sides 01' the member, a jet also arranged in said casing and connected to said compression chamber for discharging a stream of fluid from the compression chamber, a principal nozzle at the rear end of said casing, a tapered outlet pipe on said nozzle arranged co-axially to said jet for conducting the stream into the open air so that it produces a partial vacuum in the principal nozzle, a set of subsidiary nozzles, each with a curved and funnel-shaped body, arranged between said principal nozzle and said jet, with their bodies secured to said casing on the inner sidethereot, a tapered outlet pipe on each nozzle arranged co-axially to said jet and to the outlet pipe 01' the principal nozzle, the outlet pipes of the nozzles being so nested with respect to each other and to said jet, that the vacuum is gradually increased from said principal nozzle to the first subsidiary nozzle, and means operatively connected to said movable member so as, by movement of said member, to alternately connect said compression chamber to a supply 01' (I fluid under pressure and to cut of! the connection, to connect said suction chamber to the partial vacuum in the first subsidiary nozzle when the connection is established, and to connect said suction chamber to the ambient air when the connection is out 01f.

7. In a fluid-reaction propelling apparatus, a compressor, a member which subdivides said compressor into a suction and a compression chamber and is movable under the influence of the pressures acting on opposite sides of the member, a jet connected to said compression chamber for discharging a stream of fluid therefrom, a nozzle which is so arranged with respect to the jet that the stream produces a partial vacuum in the nozzle, means operatively connected to said member. so as, by movement of said member, to alternately connect said compression chamber to a supply of fluid under pressure and to cut oil? the connection, to connect said suction chamber to the partial vacuum in said nozzle when the connection is established, and to connect said suction chamber to the ambient air when the connection is cut oil, and means, also operatively connected to said movable member, for storing energy when said member moves toward said suction chamber.

8. In a fluid-reaction propelling apparatus, a compressor cylinder, a piston which is mounted to slide in said cylinder and subdivides it into a suction and a compression chamber, and is movable under the influence of the pressures acting on opposite sides of the piston, a jet con nected to said compression chamber for discharging a stream of fluid therefrom, a nozzle which is so arranged with respect to the jet that the stream produces a partial vacuum in the nozzle,

means operatively connected to said piston so as, by movement of said piston, to alternately connect said compression chamber to a supply of fluidunder pressure and to cut oil the connection, to connect said suction chamber to the partial vacuum in said nozzle when the connection is established, and to connect said suction chamber to the ambient air when the connection is cut ofi; .and a spring arranged in said suction chamber so as to be compressed when said piston moves toward said suction chamber.

9. In a fluid-reaction propelling apparatus, a compressor cylinder having ports, a piston which is mounted to slide in said cylinder and comprises a web subdividing said cylinder into a suction and a compression chamber, and a skirt having ports at opposite sides of said web for cooperation with the ports in the cylinder, which piston is movable under the influence of the pressures acting on opposite sides of said web, a jet connected to said compression chamber for discharging a stream of fluid therefrom, a nozzle which is so arranged'with respect to the jet that the stream produces a partial vacuum in the nozzle, the ports in said cylinder and in said skirt being so arranged as, by movement of said piston, to alternately connect said compression chamber to a supply of fluid under pressure and to cut off the connection, to connect said suction chamber to the partial vacuum in said nozzle when the connection is established, and to connect said suction chamber to the ambient air when the connection is cut off; and a spring arranged in said suction chamber and abutted against said web with one of its ends, so as to be compressed when saidpiston moves toward said suction chamber.

10. In a fluid-reaction propelling apparatus, a compressor, a member which subdivides said compressor into a suction and a compression chamber and is movable under the influence of the pressures acting on opposite sides of the member, a jet connected to said compression chamber for discharging a stream of fluid therefrom, means for admitting make-up air to said compression chamber, a nozzle which is so arranged with respect to the jet that the stream produces a partial vacuum in the nozzle, and means operatively connected to said member so as, by movement of said member, to alternately connect said compression chamber to a supply of fluid under pressure and to cut off the connection, to connect said suction chamber to the partial vacuum in said nozzle when the connection is established,

and to connect saidlsuction chamber to the ambient air when the connection is cut oil.

11. In a fluid-reaction propelling apparatus, a compressor cylinder, a piston which is mounted to slide in said cylinder and subdivide it into a suction and a compression chamber, and is movable under the influence of the pressures acting on opposite sides of the piston, a jet connected to said compression chamber for discharging a stream of fluid therefrom, means for admitting 2 make-up air to said compression chamber, a nozzle which is so arranged with respect to the jet that the stream produces .a partial vacuum in the nozzle, means operatively connected to said piston so as, by movement of said piston, to alternately connect said compression chamber to a supply of fluid under pressure and to cut off the connection, to connect said suction chamber to the partial vacuum in said nozzle when the connection is established, and to connect said suc- 3 tion chamber to the ambient air when the connection is cut oil; and a spring arranged in said suction chamber so as to be compressed when said piston moves toward said suction chamber.

12. In a fluid-reaction propelling apparatus, a compressor cylinder, a piston rod in said cylinder, a set of pistons secured to said rod and mounted to slide in said cylinder, a set of partitions subdividing said cylinder into a plurality of suction and compression chambers together with 4.-

said pistons, a jet connected to all said compression chambers for discharging a stream of fluid therefrom, nozzles which are so arranged with respect to the jet that the stream produces a partial vacuum in the nozzles, means operatively connected to said pistons so as, by movement of said pistons, to alternately connect one of said compression chambers to a supply of fluid under pressure and to cut ofi the connection, to connect all said suction chambers to the partial vacuum in said nozzles when the connection is established, and to connect all said suction chambers to the ambient air when the connection is cut off; and means, also operatively connected to said pistons, for storing energy when each piston moves to- 6 ward its suction chamber.

13. In a fluid-reaction propelling apparatus, a compressor cylinder, a hollow piston rod in said cylinder, a set of pistons secured to said rod and mounted to slide in said cylinder, a set of arranged with respect to the jet that the stream '76 produces a partial vacuum in the nozzles, means operatively connected to said pistons soas, by movement of'said pistons, to alternately connect one 01' said compression chambers to a supply of fluid under pressure; and to cut ofl. the connection, to connectiall said suction chambers to the ambient air when the connection is cut off and means, also operatively connected to said pistons, ior storing energy when each piston moves toward its suction chamber. 7

14. In a fluid-reaction propelling apparatus, a compressor cylinder, a set of pistons mounted to slide in said cylinder, a tubular boss on each piston which is secured to, and spaced from, said piston rod, a set of partitions subdividing said cylinder into a plurality of suction and compression chambers together'with said pistons,

each tubular boss making a sliding flt in the corresponding partition, a jet connected to all said compression chambers for discharging a stream of fluid therefrom, nozzles which are so arranged with respect to the jet that the stream produces a partial vacuum in the nozzles, means operatively connected to said pistons so as, by movement of said pistons, to alternately admit fluid under pressure to said compression chambers through said hollow bosses and to cut off the connection, to connect all said suction chambers to the partial vacuum in said each tubular boss making a sliding fit in the corresponding partition, a jet connected to all said compression chambers for discharging a stream of fluid therefrom, nozzles which are so arranged with respect to the jet that the stream produces a partial vacuum in the nozzles, means operatively connected to said pistons, so as, by movement 01' said pistons, to alternately admit fluid under pressure to said compression chambers through said hollow bosses and to cut of! 5 the connection, means including a slotted sleeve secured to said-cylinder, and a rotary valve arranged in said cylinder and operatively connected to said pistons, for connecting all said sucand means, also operatively connected to said l5 pistons, for storing energy when each piston moves toward its suction chamber.

16. In a fluid-reaction propelling apparatus, a compressor cylinder, a set of pistons mounted to slide in said cylinder, a tubular boss on each 20 piston which is secured to, and spaced from, said-piston rod, 9. set of partitions subdividing said cylinder into a plurality of suction and compression chambers together with said pistons, each tubular boss making a sliding fit in the corresponding partition, a jet connected to all said compression chambers for discharging a stream of fluid therefrom, nozzles which are so arranged with respect to the jet that the stream produces a. partial vacuum in the nozzles, means operatively connected to said pistons, so as, by movement of said pistons, to alternately admit fluid under pressure to said compression chambers through said hollow bosses and to cut off the connection, a slotted sleeve secured to said cylinder, a rotary valve arranged in said cylinder, and camming means operatively connected to said pistons for rotating said valve and connecting all said suction chambers to the partial vacuum in said nozzles when the connection is established, 4; and to the ambient air when the connection is cut oil, and for admitting make-up air to said compression chambers; and means also operatively connected to said pistons, for storing energy when each piston moves toward its suction chamber.

HANS ENDRES. 

